Lubricating gun



March 19, 41929. Q B WILSON ET AL 1,705,743

LUBRI CATING GUN Filed Oct. 8, 1927 EN R..

ATTORNEYS.

lilium@ f I Patented Mar. 19, 1929.`

UNITED STATES PATENT oFFlcE.

GEORGE B. WILSON AND KARL C. EAGLEY, OF ERIE, PENNSYLVANIA, ASSIGNORS TO. SERVICE MANUFACTURING COMPANY, ,OF ERIE, PENNSYLVANIA, A CORPORATION.

0F DELAWARE.

LUBRICATING GUN.

Application led October 8, 1927. Serial No. 224,819.

The present invention is designed to improve grease guns, particularly in the manner of operating thesame. In carrying out the invention we provide a pneumatic means which not only forces the grease forward but also affects the measuring of the'charge. The invention also contemplates a simple and etlicient means 'for re-loading the gun. Other fea( lires and details will appear more fully from the specification and claims.

A preferred embodiment of the invention is illustrated in the accompanying drawings as follows Fig. 1 shows a central section of the gun.

Fig. 2 a similar view of the charging end of the grease gun showing the parts in the position assumed after measuring a charge.

Fig. 3 a section on the line 3-3 in Fig. 1.

1 marks the gun cylinder, 2 the charging nozzle. This is secured to the cylinder 1 by a flanged coupling 3 and the discharge end v of the nozzle is provided with a screw thread 4 by which it may be attached to a bearing, or to a fitting adapting it for connection with a bearing. A cap 5 is arranged on the rear end of the cylinder 1. IThe cap has an air supply passage 6. l A valve 7 extends from the air supply passage 6 to a T 8. The T 8' has a supply hose 9 leading into it. yThe valve 7 is what is commonly known as a three-way valve provided with a plug 10 having` aV through-wayll and a cross-way 12. A valve body has a through-way 13 and an exhaustway 14. As shown in Fig. 3 the supply is turned in through the valve. With the way 12 turned -into register with the passage 13 the way 11 with the passage 14 the upper end of the cylinder may be exhausted.

A pipe y15 extends from the T 8 through a handle section 16 to the charge controlling valve 17. This valve has a body 18. A valve 19 operates on a seat 20 on the body controlling a passage 21.' The passage 21 is connected by a radial pasage 22 with a passage 23, the passage 23 leading to the lower end of a charging cylinder chamber 24. The

valve 19 has a stem 25 which extends through the passage 21 and is provided at its outer end with a head 26 on the underside of which is arranged a valve 27 operating on a seat 28 at the outer end of the passage 21. By pressing in on the head 26 thervalve 19 is opened and the valve 27 closed, the opening of the valve 19 permitting pressure to enter the charging plunger chamber 24 and releasing the'head, openlng the valve 27 exhausting this cylinder.

The plunger 29 is arranged 1n the rear end.

ofthe cylinder 1. It has the oppositely faced cups 30.

A spring 31 operates on the plunger 29, the front end of the spring being seated on a plunger 32. The plunger 321s provided with cup 33 and 1s provided with a spacing block 34 1mmed1ately under the cup 33. A char ing plunger 35 1s arranged on the spacing h ock 34 and is of greater area'than the plunger 32 and operates in the charging cylinder chamber 24. It is provided with'a cup 36. Avent openlng 37 is provided in the anged coupllng 3 for venting the space behind the plunger`35. l v

A charge forming cylinder 38 extends from' the chamber 24 and a charge forming plunger 39 operates in the cylinder 38. The plunger 39 is in the form of a sleeve and the upper enel4 'of it 4is screw-threaded and extends throu gh the plungers 32 and 35 securing these with a spacer block together. A check valve 41 operates on a seat 42 at the lower end of the plunger 39. The valve is provided with/a stem 43 which extends through the plunger and terminates with a cross bar 44 which forms a stop limiting the opening movement l gun full of'grease and air on the supply pipe. y

9, air is turned through the valve 7 into the upper end of the cylinder putting the grease under pressure. When it isdesired to deliver a charge of grease through the nozzle, the Valve 19 is opened, thus closing the'valve 26. The air under pressure is delivered into the charging plunger chamber and this operating on the plunger 35, which is of greater area than the plunger 32, forces the plunger 32 upwardly. thus forcing the plunger i29 rearwardly slightly against the air pressure 9'. The upward movement of the plunger 35 carries with it the plunger 39 and the void formed in the space under the plunger 39 is immediately `filled by a passage of grease through the plunger 39 past the check valve 41 into this space. The head 26 is then 'released, thus closing the valve 19 and opening the valve 27. The air is exhausted under the plunger and the pressure acting through the grease on the plunger 32 forces the charge ,forming plunger 39 forward, the linitial movement of this forward operation resulting in the closing of the check. valve 41 and the grease in the cavity between the check valve 41 and 45 is then subjected to a pressure equal to the air pressureacting on the entire area of the plunger 32 through the rease and plunger 29. This is readily su cient to open the check valve 45 and the charge of grease is forced forward through the nozzle with a pressure having the relation of the areas of the charge forming plunger 39 and the plunger 29 and the air pressure which, as shown, would ordinarily be very large and may be made as great as is desirable. A stop 50 is provided limitingA the forward movement of the plunger 29.

In order to fill the gun the follotving mechanism is provided: A filling fitting 48 is secured to the front end of the cylinder l. The filling fitting 48 is arranged in the cylinder opposite the stop 50 and is closed with a cap 49. By removing this ca a flexible connection, or other device, may e connected to the fitting 48 and lead from a supply of grease.

` With the plunger 29 forced to the stop 50 and the spring 31 compressed the connection through the fitting 48 is made to a grease suply and upon the release of the air pressure rom above the piston 29 the spring acting on 'this piston tends to form a vacuum -in the cylinder l and the r pressure operating on the outside supply olf grease forces it into the cylinder, thus forming a convenient means for filling the cylinder.

What is claimedv as new is y l. ln a lubricating gun the combination of a rease cylinder; a discharge nozzle on the cy inder; a forcing plunger in the cylinder; an air lconnection back of the plunger supplying fluid ressure on the plunger for forcing grease in liront of the plunger toward the nozzle; an air actuatedineans forming measured charges at'the nozzle; and devices receiving pressure from the plunger for ejecting the char e. 2. glin a lubricating un, the combination of a rease cylinder.; a ischarge nozzle on the cy inder; a forcin plunger inthe cylinder; an air connectiongback of the plunver supplying duid pressure on the plunger for forcing grease in front of the plunger toward the nozzle; a charging plunger op osing the forcing plunger, saidfcharging p unger being of larger area than the forcing lunger; an air supply means delivering air in front of the chargin plunger to force a return movement of the c erging plunger and a charge forming device actuated by the charging plunger for drawing in a charge and ejecting said charge as the air is released from the charging plunger.

3. In a lubricating gun, the combination of a grease cylinder; a discharge nozzle on the cylinder; a forcing plunger in the cylinder; an air connection back of the plunger supplying fluid pressure on the plunger for forcing grease in front of the plunger toward the nozzle; a charging plunger opposing the forcing plunger, said` charging plunger being of larger area than the forcing plunger; an air supply means delivering aixI in front of the chargmg plunger to force a return movement of the charging plunger, comprising a supply and exhaust valve operating alternately; and a charge forming device actuated by the charging plunger or drawing in a charge and ejecting said charge as the air is released from the chargin lunger.`

4. -In a lu ncating un, the combination of a grease cylinder; a ischargenozzle on the cylinder; a forcing plunger in the cylinder; an air connection back of the plunger supplying fluid ressure on the plunger for forcing grease in ront of the plunger toward-the nozzle; a charging plunger opposing the forcing plunger, said charging plunger being of larger area than the forcing plunger; an air supply means delivering air in front of the charging plunger to force a return movement of the charging plunger comprising a supply and exhaust valve operating alternately hav-` ing a passage with opposing seats; a supply valve on one seat, an exhaust valve on the other seat, and a connection between said valves; and a charge forming device actuated -by the 'charging plunger for drawing in a charge and ejecting sald charge as the air is released from the charging plunger.

5. ln a lubricating gun, the combination of a grease cylinder; a forcing lunger in the cylinder; an air connection lDeading to the cylinder back of the forcing plunger; an enlarged charging chamber connected with the cyllnder; a charging plunger of greater area t an the forcing plunger opposing the same; an air connection in front of the charging plunger; a valve for supplying andexhaustlng air 1n front of the charging plunger; a charge forming plunger operated by the charging plunger, said charge forming les plunger being hollow and forming a passage l `for grease; a check valve in the charge forming ail; in front of the chargin plunger; a er; and means fr loadin the last-mentioned charge/forming plunger operate by the char check valve to resist a d1rect pressure equal ing plun er, said.v vcharge forming plunger to the airsupply pressure. 10 being' ho `ow and forming a. passage for In testimony whereof We have hereunto set 5 grease; a checkvalve in the charge forming our hands.

plunger; a. check Valve in the nozzle opposing GEORGE B. WILSON. the check valve on the chargeforming plung- KARL C. EAGLEY. 

